The present invention relates to a well pipe for installation in a water well. More particularly, the present invention relates to a water well pipe for installation in a water well which provides for grouting between the water well pipe and the walls of the well.
Commonly, in water wells drilled in the past, a standard well pipe tubing was inserted into a pre-drilled well hole to provide for pumping of water from the drilled well by way of a pump. In installations of the past it was believed that no form of sealing means other than normal backfill in the space between the side walls of the well hole and the well pipe was necessary or desirable and therefore, was generally not provided.
In recent years however, the pollution of wells from surface contaminants entering in this backfilled space has been found to be a problem. The commonly used procedures for attempting to remedy this problem have proved to be inadequate.
For instance, the common practice today used to remedy this problem includes an inverted rubber funnel shaped boot which is attached to the base of the well pipe. The boot is designed to securely engage the pipe near the base of the pipe and to also engage the wall surfaces of the well hole. While this is somewhat effective at reducing contaminants it has two major problems. One problem is that the drilled well surfaces are not always smooth and therefore, the boot does not engage the surfaces completely. This allows gaps between the edge of the boot and the walls of the well hole where contaminants can enter. The second problem is that the boot is generally installed such that it is at the end of the well pipe which in normal practice is invariably at or below the water table. Because of this, contaminants may enter the water well above the boot which circumvents the purpose of the boot.
In other cases, well installers sometimes attempt to fill this gap by pouring a grouting material from the surface into the space. Because no efficient and inexpensive method has been heretofore disclosed which provides for a simple efficient method for grouting around the well pipe, this grouting in the past has generally been done with buckets of slurry type grouting materials such as bentonite and the like which are dumped from the surface into this gap. However, due to the depth of most wells such an application of a grouting material is inefficient at best and tends to be incomplete in that a complete filling of the spaces between the well casing and the well hole is not accomplished by these methods. Additionally, such incomplete grouting may actually be detrimental to the well because it may leave gaps in the space which could fill with water and cause freeze-thaw damage to the well pipe.
It has therefore been a goal in the water well art to provide an efficient and cost effective method for grouting substantially the entire gap between the pipe and the sides of the water well.
It is therefore an object of the present invention to provide an inexpensive and efficient method for sealing the gap between the well pipe and the well hole for preventing the entry of surface contamination into the ground water through this gap.
It is still further an object of the present invention to provide a well pipe which includes integrally formed grouting tube assemblies for injecting grout into the space between the well pipe and the drilled well hole.
Additional benefits and advantages of the present invention will become apparent from the subsequent description of the preferred embodiments taken in conjunction with the accompanying drawings.